Hydraulically powered wrenches designed for the transmission of rotational power to threaded fasteners are well known and widely used tools in industry. There are a variety of different types of power wrenches, but a typical wrench design consists of a hydraulically driven, reciprocating piston within a driver in the form of a power head unit. Hose connection couplers for receiving hydraulic fluid are positioned in relation to the piston to receive hydraulic fluid which is transmitted to the piston. Such hose couplers are generally immovably connected to the power head unit or, at best, are rotatable in a single plane, thus limiting the manner and positions in which the hydraulic tool can be connected.
Once hydraulic fluid is transmitted through the couplers and into the power head, the piston is compelled to provide the necessary motion to transmit rotational movement, through drive linkages, to drive a ratchet which then engages, to tighten or loosen, a threaded fastener.
During the period of time a threaded fastener is being tightened, it is usually necessary to brace the wrench against a stable, immoveable support structure to prevent unsafe reactive rotation of the wrench. This is often accomplished by providing a reaction arm which extends from the wrench and is designed to contact the support structure during rotation of the ratchet. Such reaction arm components are most often immovably attached to and extend out from the wrench. This configuration, however, severely limits the location and the position in which the wrench can be used, since the wrench can only be placed in an area where there is a suitably fixed support structure to safely accommodate the fixed reaction arm.
Many common hydraulic torque wrenches also are now utilizing a power head and separate, independent, link cartridge drives insertably connected within the power head. There are a variety of cartridge drives, each having different ratcheting arrangements, depending on the type of fastener which must be tightened or removed. However, the current systems do not permit power head to cartridge drive connections which are readily adaptable for quick, simple and reliable attachment of these components. In addition, current power head/cartridge drive wrench systems result in undue reactive side load and tension forces, during rotational operation of the ratchet. These forces create unbalanced, rotational torque through the wrench components which is not only dangerous, but also decreases the efficiency of the ratcheting operation and the longevity and thus the effectiveness of the tool.